Rust (iron oxide) can be found on neglected and poorly maintained grills, raising the question of whether cooking on this surface is safe? Regardless of the potential health risks, the transfer of the flaky disintegrated metal on to the food’s surface is certainly unappetizing. How can this rust be removed to provide a pristine cooking surface and are there ways to prevent the formation of rust in the first place?
Ingesting iron oxide is not harmful in moderation. Therefore, consuming food prepared on a rusty grill will not negatively impact your health unless doing so is a regular occurrence. To be safe, it is best to clean your grilling surface as best you can prior to use. This can be achieved with elbow grease, treatment with homemade remedies or with commercial-grade rust removers.
The formation and amount of rust on a grill is dependent on the type of metal that it is made from and whether you have maintained your grill. There are simple solutions to prevent rust from forming by seasoning and cleaning the grill thoroughly after use. If rust does build-up, then you can use nothing more than heat and an abrasive material to scrape it away. For excessive rust build-up, you may opt to soak the grill overnight in a variety of household mixtures or purchase a stronger chemical to restore your grill so that it looks as good as new.
The Risks of Consuming Too Much Rust
When you ingest rust, you are consuming iron oxide. An overdose of iron (generally considered as greater than 40 mg of elemental iron per kilogram of body weight) can lead to death. This is why iron poisoning is more prominent in children, whose lower body mass makes them more susceptible to iron toxicity. Iron causes such harm because it is a cellular toxin and kills cells through oxidative stress. In severe overdose cases, the kidneys of patients fail due to the cellular damage to the organ.
In adults, however, it is highly improbable that eating from a rusty grill will provide such a large dose of iron in a single meal. What is far more likely is the accumulation of iron in your bloodstream over time if you continue to use a rusty grilling surface to prepare your meals. You will start to notice that your body isn’t processing all the iron by the onset of symptoms such as abdominal pain, vomiting, diarrhea, and bleeding.
Alas, these symptoms are non-specific and may prevent a prompt diagnosis without a healthcare professional doing bloodwork. If you absolutely must ingest rust, you will want to consume as many antioxidants as you can to counteract its effects. Fruits rich in vitamin C are an excellent option for this purpose. Additionally, clean off any rust on your grilled food to keep your iron intake within the recommended daily range.
How Does Rust Form on My Grill Grate and Can I Prevent It?
These days, most grill grates are made from stainless steel which would imply that they are impervious to rust. While this is true, and the surface remains pristine, other materials on the stainless steel surface will rust. Common culprits are sauces/marinades, meat remnants, and steel wool from cleaning. From these contaminants, rust forms when the iron within them is exposed to air and moisture.
Another common source is from cleaning the stainless steel grill with a chlorine-based solution like bleach. The chlorine will break down the “passive film” on the stainless steel surface. If this is the cause, replacing the grate, in the long run, is a wise option as the rust will continuously return.
Pro Tip: Preventing rust is achievable by seasoning the metal and this is especially important if you are using cast-iron grates. To season a grill, coat the grates in fat, either from meat or by applying something like vegetable oil. Do this after each use to give the metallic surface a protective layer from the elements. If the grill is hot, avoid using an aerosol oil dispenser as it may ignite.
In addition to seasoning, keeping the grates clean is essential to preventing rust from forming. This is best done by scraping the surface with a wire grill brush, like the one I own, after each use to remove any cooking debris. Finally, keep your grill grates dry by protecting them from the elements. By following these three steps, you shouldn’t encounter rust on your grill at all, especially with stainless steel grates.
8 Methods for Removing Rust from Your Grill Grates
Despite the best preventative efforts, sometimes you will open your grill and see that the grates have rusted since their last use. You will want to remove the rust prior to cooking to prevent consuming the iron oxide.
Even though iron toxicity is extremely unlikely, especially from using a rusty grill once, for some people eating rust can lead to some digestive issues. What will be more pressing is the transfer of the degraded metal to your food and the unpalatable flavor it will deliver. So, here are eight ways to remove rust from your grill grates to ensure you always have a delicious, safe grilling experience.
1. Fat and heat
Even if you have no tools or access to any other rust removing agents, you can still clean your grill grate. In this scenario:
- Heat your grill as you normally would and leave to burn for twenty minutes. This will help break the iron oxide apart, making it easier to remove.
- Once hot, take a thick piece of fat and dab it onto the rust. You should find that larger pieces stick to the fat and can be wiped away. Repeat until no further pieces of rust are adhering to the fat.
- Before using the grate to cook your meal, use the cleaned fat to apply a final layer of grease. This will provide a protective coating between any residual rust and your food.
Pro Tip: If you don’t have a suitable piece of fat available, do your best to coat any rust that will touch your food with fat. This can be oil or butter, for example. The aim is to provide a lubricative protective layer between the corroded metal and your food.
2. Wire brush, steel wool or sandpaper
A quick and easy way to remove rust is to scrape it off using an abrasive material. Whenever you start cleaning a grill grate, always use one of these dry initially to remove as much loose rust as you can. If this alone is proving to be ineffective, each these options can be used in combination with water or with a chemical solution listed below to provide a better clean.
- First, remove the grate from the grill to prevent the rust flakes falling into the gas or coal pit. Rust tends to promote the formation of more rust, so keeping it away from your grill entirely is advisable.
- Brush each side of the grate and make sure to clean each of the crevasses. Pay particular attention to the joints as this is where rust tends to form and be the most resilient. If you are dealing with a stainless steel grate, be vigilant to not destroy the surface as this will make it more prone to rusting in the future. This can be avoided by using a finer sandpaper and always moving with the grain of the metal.
- Once all the rust has been removed, rinse the grate with water to remove any metallic particles before drying it thoroughly.
- If some rust still remains and you do not have any agents listed below, return the grill grates to the grill. Ignite the grill and allow the grates to heat thoroughly. Now, use a wire brush to scrape along the heated metal. This should help in removing the last of the rust. Allow the grates to cool and use an old rag to remove any loose rust particles.
Pro Tip: Regardless of the cleaning technique, coat the grate with vegetable oil to prevent rust from forming in the future.
3. Baking soda
Baking soda (sodium bicarbonate) is a popular chemical used in the removal of surface rust. It works by releasing oxygen as it bubbles, while it also acts as a mild abrasive. In combination with steel wool or sandpaper (or an aluminum ball or toothbrush if in a pinch), this can be highly effective at removing small areas of rust on your grill grates.
To remove rust with this method:
- Prepare a thick 10:1 paste with baking soda and water, respectively. If you have a particularity stubborn rusted area, you can substitute vinegar for the water; this will provide a stronger oxidative response and thus a higher cleaning potential.
- Apply the paste to the affected area and leave it to soak for five minutes.
- Use your chosen abrasive implement (e.g., steel wool) to apply pressure, forcing the baking soda into the rusted area.
- Rinse with water and dry after cleaning is complete.
Repeat the process as necessary.
4. Vinegar and salt
Vinegar is acidic and this combined with the abrasive action of table salt (sodium chloride) will remove rust from a metallic surface. The chlorine in the salt will not corrode the stainless steel the way chlorine in bleach does. This is due to it being chemically bound to the sodium in the salt, making it unreactive. Like all acids, the vinegar will react with the iron oxide to create a soluble iron complex.
- Start by creating a 2:1 mixture of vinegar to salt (2 cups to 1 cup). In this instance, it is best to soak the grill grates in the solution overnight. If you do not have a container large enough to hold your grill grate, use a garbage sack.
- After incubation, rinse the grill grates with water.
- Wipe off any remaining rust particles with a dry cloth.
You can use additional vinegar and salt with your sandpaper or steel wool to remove any stubborn adhered rust.
5.Citric acid and salt
If you don’t have any vinegar available, you can use the juice from a lemon, a lime or an orange mixed with salt to remove rust from your grill grate.
To do so:
- Mix in enough salt to make a thick paste and coat it over the rust affected area.
- After a few minutes, use sandpaper to work the solution into the rust with applied pressure. Quickly, you should feel the rust loosening from the surface by a reduction in resistance.
- Rinse and repeat as necessary.
The acid helps remove rust by converting the rust into soluble iron while the salt helps add a coarseness to the mix that works with the sandpaper to grinds away at the rust. Together, the causes the rust to “melt” away. Due to the limited supply of citric acid from a fruit, this method is realistically appropriate for only small sections of rust.
6. A Potato and dish soap
Using a potato as the “scrubber” is an excellent option if you are concerned about protecting the surface of your grill grate. Raw potato is abrasive and can, therefore, easily replace the sandpaper as the implement to grind away at the rust.
Potatoes also contain oxalic acid that will help lift the rust off the surface. This is due to oxalic acid converting insoluble iron compounds into a soluble iron complex. Due to this conversion, rust can literally be washed away. The dish soap offers a detergent, which will assist in loosening the rust from the grill’s surface.
Helpful Tip: If you do not have dish soap, use baking soda instead. While cleaning, if the potato-soap complex starts to feel less resistive, cut a slice off then potato to get a new surface and continue.
At some point in your life, you may have dropped a penny in soda, probably Coke, and watched as it cleaned and shined the penny to look like new. It works because some sodas contain high levels of phosphoric acid which degrades the iron-oxide complex, removing it from the surface of the coin.
The phosphoric acid will have the same effect on rust that has developed in your grill grate. For the best results, you want to completely submerge the rusted area in the soft drink. After thirty minutes, lift the grill grate out and rinse with water. For any rust that remains, use a method stated above to return your grill grate to a pristine condition.
8. Commercial rust removers
All of the previous suggestions were non-toxic cleaning options involving common household supplies. If the rust on your grill is extensive, a better option may be to purchase a commercial rust remover, like this non-toxic brand found on Amazon.
A Word of Caution: Be careful with what you buy. Some rust removers on the market will contain a highly dangerous chemical called hydrofluoric acid (HF). HF is especially dangerous if it comes into contact with your skin as it will be absorbed and bind to the calcium in your body. This is irreversible and can lead to death if you get significant amounts on your skin.
For extensive cleaning needs, you will likely be purchasing a mix containing a stronger acid than you will find in foods. As discussed, acid “disolves” the iron oxide compound, lifting it off the surface.
If you do use a manufactured product, ensure you rinse thoroughly before putting the grill grate back on your grill. When heating the grill for the first time after using the cleaning agent, check for any chemical smells or discoloration. If either is observed, rinse the grates further before using them to cook to ensure you do not ingest anything that could harm you.
Rust from a grill once in while most likely won’t harm you. It’s best though to clean your grill grates from rust. Simple household mixes can be used to achieve this, especially those that use acid and something abrasive, like salt. Whichever method you use, rinse, dry and season your grill grates to prevent any rust from forming in the future.
Can you get tetanus from a rusty grill? Tetanus (lockjaw) is caused by the bacteria Clostridium tetani that does have a rightful reputation of being present on rust surfaces. However, tetanus isn’t caused by rust, it is merely that rust tends to be outdoors which is where the bacteria reside. On a grill, if you eat the rust, you will be safe, as the temperatures reached during cooking will kill the bacterium. As always, keep your tetanus boosters up to date to protect yourself.
Which is better? A cast-iron or a stainless-steel grill? Cast iron grill grates take longer to heat up than their stainless steel counterparts, but once they are up to temperature, they stay hot longer. Cast-iron grill grates also result in grill marks that make food look desirable. However, stainless steel grills grates are easier to clean, lightweight, and more durable. There is, therefore, no right answer to which is better as it is down to personal preference and your individualized grilling needs.
What oil is best for seasoning a cast-iron grill? Cast-iron grills especially need to be seasoned to prevent rusting. Although any cooking oil or fat can be used, vegetable oil, melted shortening, or canola oil are best. This is due to their affordability, availability, effectiveness, and high smoke point.